1. Field of the Invention
The present invention relates to a punch press tool for efficiently punching out a broken sickle blade section bolt or such a bolt from which the retaining nut has been removed and pressing in a replacement bolt when replacing a sickle blade section in a windrower, swather, combine, mower or other machine or implement using a reciprocating sickle bar or strap having a plurality of blade sections attached thereto by a pair of shouldered round head bolts and nuts.
2. Description of the Prior Art
When mowing hay, grain crops and the like with a mower, windrower, swather, combine or the like, a reciprocating sickle bar with blade sections mounted thereon is associated with sickle blade guards having ledger plates thereon. Rocks, stumps and other solid obstacles are sometimes engaged causing breakage of a blade section thus necessitating removal of the broken blade section and replacing it with a new one. In some instances, the bolts holding the sickle blade section in place on the sickle bar or strap are broken in which event removal of the broken shouldered bolt is difficult and is frequently accomplished by using a center punch or other similar tool impacted by a hammer or the like. Even if the section blade bolts are not broken, removal of the retaining nuts still requires that force be applied to the upper threaded end of each of the bolts to force the bolts downwardly through the sickle bar or strap. When replacing the shouldered bolt, it is necessary to exert upward force on the rounded head of the bolt to force the bolt into the hole or opening in the sickle bar until the bolt head is flush with the lower surface of the sickle bar. This assures that the shoulder on the bolt is secured frictionally in place in the sickle bar opening thereby enabling the blade section to be assembled on the bolts and the nuts threaded onto the bolts without risk of the bolts falling out of the sickle bar during assembly of the blade section and tightening of the nuts.
The punch press tool of the present invention includes an elongated handle having a pair of rigidly interconnected, parallel links pivotally connected to one end thereof with the links being spaced apart to straddle a sickle bar. A removable transverse pin is engaged with end portions of the links in spaced relation to the end of the handle with the transverse pin being positioned below the sickle bar when the handle and attached ends of the links are positioned above the sickle bar. The handle includes a projecting heat treated pin having a short pointed end thereon spaced from the pivot axis of the handle to engage the end of a broken bolt in a sickle bar, or the upper end of a bolt from which the nut has been removed, to force the bolt downwardly out of the opening in the sickle bar when the handle is pivoted toward the sickle bar.
The tool also is used to force a new shouldered bolt upwardly into the sickle bar opening with the round head of the bolt engaging flush with the bottom of the sickle bar. In this use, the transverse pin is removed and the handle and its pivotal connection with the links are positioned below the sickle bar with the links straddling and extending above the sickle bar. The removable transverse pin is inserted through the ends of the links above the sickle bar. The handle includes an edge surface having a protruding end edge to engage and initially move the bolt into an opening in the sickle bar. The edge surface of the handle also includes a short flat surface which finishes movement of the bolt into flush engagement with undersurface of the sickle bar and frictionally locks the bolt in the sickle bar opening.
The present invention enables the efficient replacement of a sickle blade section without removal of the sickle bar or strap. In this procedure, a single guard is removed thereby providing sufficient space to utilize the tool of the present invention to punch out a shouldered bolt, even if broken. Then a new bolt can be inserted by exerting pressure on the round head of the new bolt to force the bolt shoulder into the opening in the sickle bar or strap to frictionally retain the bolts in the sickle bar. A new blade section is then placed on the bolts and retaining nuts are placed on the upper ends of the bolts.
It is therefore an object of the present invention to provide a punch press tool for replacing sickle bar blade section retaining bolts when the bolts have been broken or when the retaining nuts on the upper ends of the bolts have been removed to enable a new blade section to be mounted on the sickle bar or strap without removing the sickle bar or strap from the mower or other implement with one guard being temporarily removed to provide access to the upper and lower surfaces of the sickle bar in the area where the blade section is to be replaced.
Another object of the invention is to provide a punch press tool including an elongated handle having a pair of laterally spaced, parallel links pivotally mounted at one end thereof with the links being spaced apart sufficiently to straddle the sickle bar or strap. The ends of the links spaced from the pivotal connection with the handle includes aligned apertures receiving a removable transverse pin positioned on the opposite surface of the sickle bar or strap from the pivotal connection of the links to the pivotal handle.
A further object of the invention is to provide a punch press tool in accordance with the preceding objects in which the end of the handle includes a radially projecting pin having a sharp point at its outer end. The pin with sharp point is spaced from the axis of the pivotal connection between the handle and links. A removable transverse pin is engaged with outer ends of the links to enable the pivotal connection between the links and handle to be placed either above or below the sickle bar or strap. When the handle is placed above the sickle bar or strap, the projecting pin thereon can be aligned with the end of the bolt, even if broken, and downward pressure exerted on the handle forces the bolt downwardly out of the opening in the sickle bar or strap. When a new bolt is being placed in the sickle bar or strap, the handle and the pivotal connection with the links are positioned below the sickle bar with the links straddling and extending above the sickle bar to enable the removable transverse pin to be inserted through the upper ends of the links above the sickle bar. When positioning the handle below the sickle bar, the handle is flipped over to position the radial pin on the handle remote from the bolt head and position the end edge of the edge surface of the handle adjacent to the bolt head. The bolt can then be manually placed in the sickle bar opening and held in position with one hand with the other hand pivoting the handle upwardly. This will engage the end edge of the edge surface of the handle with the bolt head. Further pivotal movement of the handle upwardly exerts upward force on the bolt head by a juncture point between the end edge of the handle and an adjacent eccentric flat surface. Movement of the bolt head into flush engagement with the undersurface of the sickle bar causes the shoulder on the bolt to frictionally and lockingly engage with the periphery of the opening in the sickle bar to enable a new blade section to be placed on the bolts and nuts placed on the bolts and tightened.
A still further object of the invention is to provide a punch press tool which materially reduces the down time of a farm implement or other apparatus utilizing a reciprocating sickle bar with blade sections mounted thereon by enabling removal of shouldered bolts, either broken or with the nuts removed, and then placing new shoulder bolts in position for attachment of a new blade section in an efficient, effective and less time consuming manner.
Yet another object of this invention to be specifically enumerated herein is to provide a punch press tool in accordance with the preceding objects which will conform to conventional forms of manufacture, be of simple construction and easy to use so as to provide a device that will be economically feasible, long lasting and relatively trouble free in operation.
These together with other objects and advantages which will become subsequently apparent reside in the details of construction and operation as more fully hereinafter described and claimed, reference being had to the accompany drawings forming a part hereof, wherein like numerals refer to like parts throughout.